Peropyrene compounds, as large polycyclic aromatic hydrocarbons (LPAH), comprise structural features that convey unique photophysical properties to such compounds. However, due to difficult preparation and derivatization of such compounds, their utility has yet to be utilized in various applications. Perylenediimide derivatives, which comprise a similar core as peropyrene compounds, have been prepared and analyzed. Chiral conjugated molecules are a class of interesting research as these molecules have utility in areas such as polarized photoluminescence, enantioselective sensing, etc. Methods exist to introduce chirality into conjugated materials, including appending a chiral auxiliary, or synthesizing an LPAH that is twisted giving rise to axial chirality, such as seen in helicenes. For example, axial chirality in twisted perylenediimide derivatives has been observed where substituents on the cove positions cause twisting of the PAH to relieve steric strain. This is seen even if the substituent is a hydrogen, albeit, with a low barrier to inversion of enantiomers. There is a need in the art, however, for methods to introduce chirality into peropyrene molecules.
Other aromatic ring systems comprising peropyrene cores also are of interest, such as graphene, an organic material comprised of a 2-dimensional monolayer of sp2-hybridized carbon atoms. Graphene has been shown to have interesting electronic, thermal, mechanical, and optical properties. The properties of graphene materials can be altered by varying the size and shape of the graphene sheets. These materials are of interest for device applications such as thin-film transistors (TFTs) and field-effect transistors (FETs) due to their interesting electronic properties. Specifically, graphene is a zero band-gap semiconductor whereas graphene nanoribbons have a persistent band-gap making them useful material in thin-film transistors (TFTs). One particular area of interest is the scission of graphene sheets into thin strips known as graphene nanoribbons that have different properties than graphene. The approach of exfoliation of graphite to produce graphene, followed by scission of graphene is known as a “top-down” approach. These methods result in mixtures of different sizes and shapes of graphene nanoribbons and the products typically have poor solubility, making processing of the material for device applications difficult. Also, the harsh conditions used to produce graphene nanoribbons using a “top-down” approach (lithographic patterning of graphene or unzipping of carbon nanotubes) can result in oxidized graphene nanoribbons, which significantly affects the electronic properties of the material. Thus, there is a need in the art for methods of making graphene nanoribbons that can address these drawbacks.